Infrared
In the electromagnetic spectrum, Ultraviolet (UV) and infrared (IR) are both invisible rays that exist on opposite sides
of the visible light. UV is known to initiate the photochemical reaction with DNA and RNA, often used for sterilization and
disinfection purposes. IR produces thermal therapeutic effects that are often used for clinical rehabilitation and treatment.

Far-Infrared
According to the difference in wavelengths, IR could be roughly divided into Near and Medium-Infrared and Far-Infrared; the difference in wavelengths also contributes to the significant difference in their properties.
Due to its higher frequency, NIR has higher power density and generates more heat, thus often used for quick drying
and high-temperature firing. On the other hand, FIR has lower power density and generates less heat,
though its penetrability is weaker, it is more readily absorbed by the human body.

Low Power Density
The electromagnetic energy of FIR Company's far-infrared unit is distributed between a wide spectrum from 3µm to 25µm with peak value around 8µm.
Despite its remarkable therapeutic effects, the power density of FIR is only at milliwatt level and its energy grade is far
below that of the more familiar infrared (Near-Infrared) rays.

Energy Transfer With Resonance
When far-infrared (FIR) rays irradiates the human body, some are reflected and the rest are fully absorbed by the skin.
Due to the similarity in wavelengths between FIR rays and that of water and protein, the energy from the irradiation
initiates energy resonance within the tissues that enhances further energy absorption, which results in an increase
in topical temperature.

Thermal and Non-Thermal Effects
The physical responses induced by the topical temperature elevation following FIR irradiation are described as thermal effect.
However, FIR is believed to initiate more than just thermal effect. There are some consequential responses observed in
FIR clinical application and animal studies that cannot be explained or comprehended by thermal effect alone,
including the FIR energy transfer mechanism in the tissue level, and these processes are described as non-thermal effect.
The fascinating nature of FIR has remained the hot topic for researchers in recent years.